Criminal psychology is the study of the wills, thoughts, intentions and reactions of criminals. The study goes deeply into what makes someone commit crime, but also the reactions after the crime, on the run or in court. Criminal psychologists are often called up as witnesses in court cases to help the jury understand the mind of the criminal. Psychiatry also may deal with aspects of criminal behavior.

Some have criticized criminal psychology as subjective, isolating, and implicating intractable identities. Among the most notable people who criticized how psychology and psychiatry treated crime as an identity is FrenchphilosopherMichel Foucault. Among other issues relating to criminality, Foucault was critical of prison systems and the use of punishment as determent to crime. Other detractors using the frame espoused by Foucault claim that isolating those who break laws into a particular class only manifests more criminal behavior.